Atomizer for liquids in general and in particular for liquid fuels



BEST AVAILABLE COPY P. PULIDQR! ,0

R FOR LIQUIDS IN GENERAL AND IN PARTICULAR FOR LIQUID FUELS April 4-, 1939.

ATOMIZE Filed NOV. 25, 1936 BEST AVAILABLE COPY UNITED STATES PATENT GFFICE ATOlWIZER FOR LIQUIDS IN GENERAL AND IN PARTICULAR FOR LIQUID FUELS Palmiro Pulidcri, Florence, Italy Application November 25, 1936, Serial No. 112,671 In Italy December 7, 1935 3 Claims.

It is a well-known fact that if any liquid under pressure be caused to pass through a calibrated aperture, same issues from such aperture subdivided into the most minute particles.

In certain cases it is not sufiicient to simply subject the liquid to pressure, but it is necessary that a whirling motion be imparted to same, for the purpose of obtainingon the liquid issuing from the aperture-a hollow cone, which will prove more or less ample. according to the whirling motion to which the liquid tobe atomized has been subjected.

The invention concerns, precisely, a means for the obtainment of a jet of atomized liquid, this means comprising helicoidal and spiral passages for the liquid, preceding the egress of same, and which allow of better atomization.

All this is secured without any capillary apertures, through simple and practical means such as to admit of the adoption of ample passages, which are thus not easily obstructed by eventual impurities contained in the liquid.

Essentially, the invention consists in providing the liquid admission channel with a head having internally, a multi-principled screw, or other means, constituting a suitable passage-way capable in any case of compelling the liquid to become thoroughly well mixed within a chamber, out of which latter the liquid thus mixed or blended re-issues for the purpose of traversing a conduit in the form of an Archimedean spiral and thereupon issuing through a small aperture, with a whirling motion.

In one preferred form of embodiment, the liquid to be atomized after having traversed the spiral Archimedean passage, and. before issuing through the small aperture or nozzle of the calibrator may flow into a small chamber on which centre there is a post coaxial and concentric with the part carrying the said Archimedean spiral passage-way. This post or small column is in any case carried by the small spiral-carrying plate and stands upon the part upon which the said Archimedean spiral channel is cut.

By means of the said post, whose diameter is appropriately determinate, eventual retardations are avoided in the whirling chamber of the velocity having been acquired by the liquid during its passage through the Archimedean spiral channel, regurgitations being likewise avoided, or impediments to the regular outflow of the fluid while traversing the whirling chamber, bebore reaching the nozzle of the calibrator.

The fluid in motion, on issuing from the Archimedean spiral channel, therefore winds round the post before arriving at the outlet nozzle.

When the post is fixed to the small Archimedean spiral plate, so that said post is unable to perform any movement, its function is that indicated above; if, however, the post be rendered movable about the axis thereof, by means of any suitable arrangement, it may, in addition to performing the aforesaid functions, also serve as a pin for diminishing or intercepting the passage of the fluid through the nozzle of the calibrator.

All this is obtained through a few, demountable and readily cleanable parts.

The invention will be more precisely intelligible on following the accompanying drawing, which is supplied solely as a practical example of the carrying out of the invention.

In said drawing:

Fig. 1 shows, in a plan View, a disk provided with an Archimedean spiral, with a central post;

Fig. 2 shows, in vertical section, on line A-B of Fig. 1 a calibrator with the relative disk provided with an Archimedean spiral channel and with a fixed central post;

Fig. 3 shows, still in vertical section, a calibrator and the relative disk provided with a post being shiftable upon the centre of the Archimedean spiral;

Fig. 4 shows in vertical section, an atomizer provided with a central screw shaft;

Fig. 5 shows, still in vertical section a calibrator and the relative disk in which the central supporting post is extended beyond the calibrator and Fig. 6 shows, still in vertical section, a variation of the example according to Fig. 5.

In the example represented in Figs. 1 and 2 it will be seen that on the disk 2 there is traced the Archimedean spiral in such a manner as to leave, at the centre, a chamber 4 of sufiicient diameter. The spiral commences at 5 viz. in the aperture which traverses the entire thickness of the small plate 2 whereas the spiral proper presents a thickness and a depth determined according to each single case.

To the centre of the chamber 4 which will be found co-axial and concentric with the small plate, there is appliedin any mannera post or small column 6 of such dimensions as to leave free-round about samea space that may be equal to the width of the Archimedean spiral, as it might be greater or less than the latter.

The overlying calibrator l carries, in register of course, with the post 6, a duct 8 of suitable shape, hemispherical, for instance, from which duct the fluid escapes through the nozzle 9,

the small plate 2 and secured by' a nut ill but it could also be riveted or anyhow locked.

On examining Fig. 3 it will be seen that the small post or column 6 consists in a shaft ll provided with a number of annular grooves E2 in function of a labyrinth, which shaft is threaded into an appendage l3 carried by the disk 2, the said shaft terminating at its upper part in some suitable form, being hemispherical or conical, for instance. This shaft is shiftable within the appendage it so as to regulate the outflow of the liquid issuing from the orifice 9.

In Fig. 4 there is seen an atomizer in which there is screwed to the appendage it of the small plate 2 provided with the Archimedean spiral, a shaft M which--like that marked llfulfils the function not only of guiding the whirling motion, but also of regulating the issue of the outflow from the orifice 9 of the calibrator 7.

In Fig. 5 it will be seen that the calibrator 1 presents an ample aperture through which there passes-while leaving a slight intervening annular space-a post which is screwed to the small plate 2 but projects from said calibrator I.

In this case the outflowing fluid forms a perfeet circular wreath.

As will further be seen in the said figure, the post i5 is in the shape of a truncated cone, while the walls both of the chamber l and those of the aperture of the calibrating portion are vertical.

In Fig. 6, on the contrary, the wall of the chamber 5 is vertical, whereas the wall of the calibrator l is in the shape of a truncated cone converging upwardly (when observing the drawing) for the purpose of corresponding with those of the chamber 5, and terminates vertically at its upper part, leaving, (in this vertical portion it) an annular intervening space between the wall itself and the post ll which-in this case-is perfectly cylindrical.

In this example likewise, the fluid issuing through the said intervening space forms as it were a circular wreath.

It is clear that the pin or post may extend as far as the aperture of the calibrator, while it may also pass beyond same.

According to what has been set forth it therefore always emerges, and from every example, that the atomizer is based upon the idea of a simple (preferably Archimedean) spiral passage- Way-that starts from the periphery of the disk into which it is cut, to arrive at the whirling chamber located at the centre of same, provided, preferably, with a central pin or post, being fixed or movable, projecting, or not, beyond the upper part of the calibrator with a head of any suitable shape, hemispherical, for instance, conical or even flat.

As in the arrangement in question but one spiral passage-way is provided, it is preferable that same be traced according to the law of the Archimedean spiral, in contradistinction to other forms of tracing (for instance, the logarithmic, the hyperbolic spiral, etc.) because the i H Archimedean spiral tracing, in the case of a In Fig. 2 the post 6 is indicate'das screwedto single" spiral, affords the best results from the point of view of the practical operation of the apparatus, while presenting the least difiiculty of construction, as the cutting of the channel into the small platein the case of an Archimedean spiral-may be effected directly on a lathe without any necessity of recourse being had to any special devicessuch as pantographs or the likefor the cutting of the above channel; such as are necessary, on the contrary, in case the tracing were not that of an Archimedean spiral.

In cases where the atomizer is required to function with large quantities, and in order that the diameter of the bore shall not be excessively increased, the arrangements indicated in Figs. 5 and 6 are suitable; in effect, through the extension of the post to beyond the orifice of the calibrating portion and the appropriate increase of the diameter of said orifices or bore, so as to create a certain intervening space between the calibrating portion and the post (l5 and IT) the outflow section for the fluid to be circulated is converted into that of a circular rim. Thus the fluid is compelled to undergo a real lamination, as it were, during its passage through the said annular intervening space.

In the case of the device being used as a burner, it is evident that the cone constitutes when appropriately lighted-the ignition cone.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is:

1. In a spray nozzle for finely dividing liquids the combination with an intake and a calibrated central discharge passage, of a centrally disposed whirl compartment opening into said discharge passage and having a larger cross section than the latter, a central chamber registering with said whirl compartment, an. element intermediate said intake passage and said central chamber, said intermediate element providing a path in the form of an Archimedean spiral the outer end thereof communicating with said intake passage and the inner end opening into said central chamber, and a pin arranged coaxially to said spiral path in said central chamber, said pin having a hemispherical head projecting into said whirl compartment and forming a guide for the rotating liquid entering said central chamber after having passed said spiral path.

2. A combination, as claimed in claim 1, in which said pin is adapted to be displaced in the direction of its own longitudinal axis so as to project more or less into said whirl compartment in order to regulate the discharge of the liquid.

3. A combination, as claimed in claim 1, in which said pin projects through said whirl chamber into the calibrated discharge passage thereby leaving an annular discharge duct between its outer periphery and the inner periphery of said discharge passage.

PALIWIRO PULIDORI. 

